Relationships among dissolved organic matter, iron, and discharge in a moorland stream

Abstract

Dissolved organic matter (DOM) and iron in a moorland stream were determined at 8-hour intervals over a 6-month period to examine relationships with streamflow. Regression of both solutes on discharge were positive and explained per cent of the variance in the solute data, but better predictions were obtained in both cases when a covariate reflecting temporal variation in the relationships was introduced (explained variance 8&90 per cent). Variations in the regression of Fe on DOM were also identified, indicating differences in the complexing power of DOM for Fe and possible variations in the chemical composition of the DOM.

Concentrations and annual loading of dissolved organic matter in a small moorland stream

“…The significance of soil water as a source of DOM has also recently been discussed by Hynes (1983), who emphasized the role of the stream bed {hyporheic zone) as a sink for such inputs. The concentration of dissolved iron and its strong relationship with organic matter (Grieve, 1984) is a further pointer to the significance of the soil as a major source of organic matter.…”

“…Vegetation is grass moor with some blanket bog and soils are peaty. Further details were given by Grieve (1984).…”

“…Larson (1978) indicated maxima in autumn and late winter, and Grieve (1984) reported an early autumn maximum on the basis of more detailed sampling over a 6 month time period. Thus unless sampling schemes are sufficiently intensive to include storm events and of sufficiently long duration to include all seasons of tbe year, estimates of annual organic matter loss in streamflow are likely to be severely biased.…”

Potential of turbidity monitoring for measuring the transport of suspended solids in streams

“…The available evidence indicates that water colour [or the concentration of gilvin or dissolved organic carbon (DOC)] increases during storm event runoff and gradually decreases as discharge recedes (Baker et al, 1974;McDowell and Fisher, 1976;Larson, 1978;Lush and Hynes, 1978;Dahm, 1981;Foster and Grieve, 1982;Tate and Meyer, 1983;Grieve, 1984;Eshleman and Hemond, 1985;Bowles et al, 1986;Taylor and Adams, 1986;Lawrence et al, 1988;McDowell and Likens: 1988;Gippel, 1989a). Gilvin and the suspended solids concentration have different source areas (Gippel, 1987) and temporal variations in their concentration are probably only broadly related (Gippel, 1989a).…”

Dynamics of dissolved organic carbon in forested and disturbed catchments, Westland, New Zealand: 1. Maimai

“…Storm sampling of the Maimai streams shows that DOC concentrations are higher on the rising than the falling limb of the hydrograph, a pattern noted by McDowell and Fisher [1976] in a small, temperate, hardwood catchment in Massachusetts. However, the reverse pattern has been recorded in the Larry River catchments near Reefton [Moore and Jackson, this issue] and in a Scottish moorland stream [Grieve, 1984b]. Meyer and Tare [1983] found variable patterns in catchments at Coweeta.…”